Ink ribbon reversing mechanism for business machines



J1me 1942- H. NEUMANN-LEZIUS INK RIBBON REVERSING MECHANISM FOR BUSINESSMACHINES Filed Sept. 28, 1940 INVENTOR 4 ATTORNEY Patented June 2, 194 2INK RIBBON REVERSING MECHANISM FOR 7 BUSINESS MACHINES HansNeumann-Lezius, Berlin-Lankwitz, Germany, assignor to InternationalBusiness Machines Corporation, New York, N. Y., a corporation of NewYork Application September 28, 1940, Serial No. 358,895 In GermanyJanuary 16, 1940 4 Claims.

This invention relates to reversing mechanism for-the printing ribbon ofa business machine. According to the present invention, as the ribbon iswound upon one spool, a follower is actuated by the increasing roll ofribbon and a spring is tensioned to store energy. When the oppositespool is depleted, +etrailing end of the ribbon, through a suitable clipor fastening, trips a latch and releases the stored energy to cause theac,- tual reversal of the driving mechanism.

Other objects of the invention will be pointed out in the followingdescription and claims and illustrated in the accompanying drawing,which discloses, by way of example, the principle of the invention andthe best mode, which has been contemplated, of applying that principle.

In the drawing:

shown by means of a latch II. which is pivoted at l3 to an extension I!of the plate H. The latch ll engages in a notch I in the lower extremityof the arm 9, and the spring M (Fig. 3) normally bears upon the latch IIto hold it in latching position in the notch l0. There are two latchesll provided, one to hold the lever 2 in the position shown and the otherto hold the Fig. 1 is a view of the assembled mechanism.

Fig. 2 is a' view looking from the bottom of Fig. 1.

Fig. 3 is a section taken along line 3-3 of Fig. 1.

In the drawing l1 represents the usual plate upon which the variousparts are mounted, this plate being suitably attached to the printingmachine. A pair of ears l8 extending from the plate'serves to supportthe slidable shaft 15 to which is secured a ratchet It. This ratchet isadvanced step by step in the usual manner by means of any suitable'pawldevice so as to advance the ratchet one step for each operation of theprinting mechanism.

The opposite ends'of shaft l5 carrybeveled gears 26 which mesh withbeveled gears 22 on the spindles 2| which carry'the ribbon spools I.

An arm 2 pivoted at 3 to the plate J! has integral therewith an ofi'setarm 9 which extends through a groove formed by flanges I9 on the shaftl5. This arm 2, when rocked about pivot 3, serves toshift shaft l5 totransfer the driving connection from one of the spools to the other.

A pair of follower members comprising arms 5 and 5 are pivoted on studs8 in the plate l1. The upper ends of the arms 5 are connected by springsl to the upper extremity of the pivot arm 2. The arms 6 are arranged tolie in the path of the ribbon and to extend between the flanges of theribbon spools so as to be acted upon by the ribbon as it accumulatesupon the spool as shown in Fig. 1, where a full spool has rocked theassociated arm 6 and caused tensioning of the related spring I while onthe opposite side the exhaustion of the ribbon has released the tensionin itsassociated spring I.

The arm 2 is normally held in the position lever in. its alternateposition. It will thus be seen that with the lever 2 latched in theposition shown, the left hand spring I will exert pressure upon the armas the left hand spool accumulates the ribbon, and the opposing spring Igradually loses its tension as the related spool is unwound.

The manner in which the arm 2 is unlatched to effect reversal of thedrive will now be explained. A latch-releasing plate 23 is provided,which is mounted for reciprocation upon the plate II by means of studs24. The extremities of the plate are bent and slotted to provide a guidethrough which the inked ribbon 4 passes. The upper edge of plate 23 hastwo converging inclines designated 25 and 250. which are in line withone arm of the latch H (see Fig. 3). When the lever 2 is in the positionshown, the latch 23 is toward the left with the low point of the inclinein line with the left hand latch ll, so

that the spring I will hold the lever in the clockwise position shown inFig. 3. If the latch plate 23 is now moved toward the right as viewed inFig. 1, the extremity of the left hand lever II will be cammed upwardlycausing depression of its opposite end and consequent release of the arm9.

Such movement of plate 23 is brought about by the ribbon itselfthroughthe medium of a stop 26 fastenedto the ribbon. When this stopengages the slot in plate 23, the plate will be carried along with theribbon and will actuate the latch II as described. Upon such release thetensioned left hand spring I will cause shifting of the drive shaft l5,so that the ribbon spool will With this arrangement the ribbon has thecomparatively light task of rocking latch l I, and r the actual work ofreversing the drive is effected by the springs l in which the necessaryenergy is gradually accumulated as one or the other of the spools windsup the ribbon.

While there has been shown and described and pointed out the fundamentalnovel features of the invention as applied to a single modification, itwill be understood that various omissions and substitutions and changesin the form and details of the device illustrated and in its operationmay be made by those skilled in the art without departing from thespirit of the invention. It is the intention, therefore, to be limitedonly as indicated by the scope of the following claims.

What is claimed is: r

1. In a ribbon reversing mechanism having a pair of spools and ashiftable drive member positionable to drive either spool, thecombination of a pivoted lever coacting with the drive member to shiftthe same, latching means to hold the lever in either of its twopositions, a follower for each spool engageable with the ribbon, atension spring between each follower and said shift lever, the follower,associated with the spool upon which the ribbon is winding, being causedby the ribbon to tension its related spring, and means controlled by theribbon as it unwinds from the opposite spool for releasing said latchingmeans whereby the tensioned spring will actuate the shift lever toreverse the drive for the spools.

2. The invention set forth in claim 1 in which the means controlled bythe ribbon comprises a slidable bar movable forreleasing the latchingmeans and both ends of the ribbon are provided with clips which move thebar to release the latching means.

3. In a ribbon reversing mechanism having a pair of spools and ashiftable drive member positionable to drive either spool, latchingmeans to hold the member in driving relation with either spool, afollower for each spool engageable with the ribbon, a pair of springsone connected to each follower and both arranged to act upon said drivemember, the follower associated with the spool upon which the ribbon iswinding being caused by the ribbon to tend to urge the member toward itsalternate position by means of the related spring, and means controlledby the ribbon as it unwinds from the opposite spool for releasing saidlatching means whereby said member will be urged by the spring intoposition to reverse the drive for the spools.

4. In a ribbon reversing mechanism having a pair of spools and ashiftable drive member positionable to drive either spool, thecombination of a lever coacting with the drive member to shift the same,latching means to hold the lever in either of two positions, a followerfor each spool engageable with the ribbon, a spring between eachfollower and said lever, the follower, associated withthe spool uponwhich the ribbon is winding, being caused by the ribbon to store energyin its related spring, and means controlled by the ribbon as it unwindsfrom the opposite spool for releasing said latching means whereby thespring will actuate the shift lever to reverse' the drive for thespools. v

HANS NEUMAN'N-LEZIUS.

